摘要

食品工业中抗生素抗性细菌的出现需要用有效的抗菌剂控制。在这项研究中，细菌素MN047A（BMA）被发现对多重耐药细菌具有抗菌活性。它首次从中国新疆传统发酵乳制品马奶酒分离的乳杆菌 MN047生产。通过硫酸铵沉淀，离子交换色谱和反相色谱纯化。根据基质辅助激光解吸/电离飞行时间质谱，其具有1,770.89Da的低分子量，并且通过液相色谱 - 串联质谱分析和MASCOT搜索将该序列鉴定为QLPWQILGIVAGMFQA。它本质上是蛋白质的：细菌素被蛋白酶消化，但不被α-淀粉酶或脂肪酶消化。它具有广泛的pH耐受性（pH 2-11），良好的热稳定性和良好的储存稳定性。它具有广泛的抑制谱，包括革兰氏阳性和革兰氏阴性细菌。生长曲线和时间 - 杀灭动力学表明它对指示菌株有杀菌作用，用BMA处理后扫描电镜和透射电镜证实了这一发现。同时，根据流式细胞术的细胞周期分析，BMA阻止了金黄色葡萄球菌和大肠杆菌在G1期和G2 / M期的生长，表明BMA对食源性病原体具有全面的抑制作用。

The growing emergence of antibiotic-resistant bacteria in the food industry needs to be controlled with effective antimicrobials. In this study, bacteriocin MN047 A (BMA) was found to have antibacterial activity against multidrug-resistant bacteria. It was produced by Lactobacillus crustorum MN047, which was first isolated from koumiss, a traditional fermented dairy product from Xinjiang Autonomous Region, China. It was purified by ammonium sulfate precipitation, ion-exchange chromatography, and reversed-phase chromatography. It had a low molecular mass of 1,770.89 Da according to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and the sequence was identified as QLPWQILGIVAGMFQA by liquid chromatography–tandem mass spectrometry analysis and MASCOT searching. It was proteinaceous in nature: the bacteriocin was digested by protease but not by α-amylase or lipase. It showed broad pH toleration (pH 2–11), good thermostability, and good storage stability. It had a broad inhibitory spectrum, including both gram-positive and gram-negative bacteria. Growth curve and time-kill kinetics indicated that it was bactericidal to the indicator strains, and this finding was verified by scanning electron microscope and transmission electron microscope after treatment with BMA. As well, BMA halted the growth of Staphylococcus aureus and Escherichia coli in the G1 and G2/M phases according to cell-cycle analysis by flow cytometry, indicating that BMA had comprehensive inhibitory effects against foodborne pathogens.

https://www.journalofdairyscience.org/article/S0022-0302(16)30441-6/fulltext